A common crimping terminal is provided at the front portion thereof with an electric connection portion for connecting to a mating terminal and the like, and at the rear portion thereof with a wire connection portion that is caulked and connected to a terminal portion of an electric wire. The wire connection portion usually has a structure in which a conductor crimping portion is arranged on the front side thereof and a sheath caulking portion is arranged at intervals in the rear side thereof. The conductor crimping portion and the sheath caulking portion each are provided with a bottom plate and a pair of caulking pieces extended upwardly from both side edges of the bottom plate so as to have a substantially U-shaped cross section. The caulking piece of the conductor crimping portion and the caulking piece of the sheath caulking portion are spaced apart independently of each other.
However, in such a crimping terminal, since the caulking piece of the conductor crimping portion and the caulking piece of the sheath caulking portion are spaced apart from each other, there has been a possibility that the wire conductor is exposed between the conductor crimping portion and the sheath caulking portion when the caulking piece of the conductor crimping portion is bent inwardly to crimp the conductor having been exposed by removing an insulation sheath of the terminal portion of the electric wire, and at the same time, when the caulking portion of the sheath caulking portion is bent inwardly to caulk an insulation-sheath portion, there is a possibility that moisture is adhered to the exposed conductor portion thereby leading to corrosion thereof.
A crimping terminal for solving the problems has been proposed in Patent Document 1 as described therein. FIGS. 23A and 23B show the configuration of the crimping terminal described in Patent Document 1, FIG. 24 shows the state where the crimping terminal is connected to the terminal portion of electric wire, and FIG. 25 shows the problem of the crimp terminal having been described in Patent Document 1.
As shown in FIGS. 23A and 23B, and FIG. 24, the crimping terminal 110 is provided in the front portion thereof with an electric connection portion 111 for connecting to a mating terminal (not shown) and the like, and in the rear portion thereof with a wire connection portion 112 that is caulked and connected to the terminal portion of the electric wire W, and the wire connection portion 112 and the electric connection portion 111 are integrally connected therebetween to a connection portion 113.
The wire connection portion 112 is provided with a conductor crimping portion 114 that is located in the front side thereof and a sheath caulking portion 115 that is located in the rear side thereof. The conductor crimping portion 114 is formed so as to have a U-shaped cross section with a bottom plate 121 and a pair of conductor caulking pieces 122 which are extended upwardly from both side edges of the bottom plate 121 and bent inwardly to enclose a conductor Wa having been exposed by removing the insulation sheath Wb of the terminal portion of electric wire W to be connected thereto thereby caulking the conductor Wa so as to be in close contact with the upper surface of the bottom plate 121. Similarly, the sheath caulking portion 115 is formed so as to have a U-shaped cross section with a bottom plate 123 and a pair of sheath caulking pieces 124 which are extended upwardly from the both side edges of the bottom plate 123 and bent inwardly to embrace a portion covered by the insulation sheath Wb of the terminal portion of the electric wire W to be connected thereto thereby caulking the insulation sheath Wb portion of the terminal portion of the electric wire W so as to be in close contact with the upper surface of the bottom plate 123. The bottom plate 121 of the conductor crimping portion 114 and the bottom plate 123 of the sheath caulking portion 115 are formed with a common continuous bottom plate via an electric connection portion 113 from the electric connection portion 111. In addition, the conductor crimping portion 114 is provided on the inner circumferential surface thereof with a serration 131 to increase the continuity of contact with the conductor Wa of wire W.
And, as a characteristic point of the crimping terminal 110, the conductor caulking piece 122 of the conductor crimping portion 114 and the sheath caulking piece 124 of the sheath caulking portion 115 are provided therebetween with a covering wall 117 that is plastically deformed so as to cover the portion between the conductor press-camping portion 114 and the sheath caulking portion 115 according to the caulking process of the conductor caulking pieces 122 and the sheath caulking pieces 124. In other words, the covering wall 117 is formed with a continuous wall that is integrally formed continuously from the conductor caulking pieces 122 of the conductor crimping portion 114 to the sheath caulking portion 124 of the sheath caulking portion 115.
Here, the upper end edge of the covering wall, which is continuously formed from the conductor crimping portion 114 to the sheath caulking portion 115, is formed in a straight line shape extended obliquely relative to the longitudinal direction of the bottom plate portions 121, 123 because the upper end edge of the conductor caulking piece 122 of the conductor crimping portion 114 is positioned lower in its height than the upper end edge of the sheath caulking piece 124 of the sheath caulking portion 115.
According to the crimping terminal 110, as shown in FIG. 24, the covering wall 117, which is provided between the conductor crimping portion 114 and the sheath caulking portion 115, serves to cover the conductor Wa of the electric wire W having been exposed between the conductor crimping portion 114 and the sheath caulking portion 115 in a state where the crimping terminal 110 is crimped to the terminal portion of the wire W, thereby preventing moisture or dust from being adhered thereto, as a result, the problem of corrosion of the conductor Wa can be suppressed.